Telescoping closed-tube sampling assembly

ABSTRACT

A clinical diagnostic sample analyzer for analyzing a sample of a patient is disclosed. The analyzer includes a telescoping closed-tube sampling assembly with a sample probe concentrically housed within a piercing probe and a venting mechanism. The closed-tube sampling assembly is used for aspirating a sample from a sample tube for analysis by a clinical diagnostic sample analyzer.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation application of a application Ser. No.11/417,770, filed on May 4, 2006, now granted U.S. Pat. No. 8,758,702issued on Jun. 24, 2014, which claims priority to and benefit of U.S.Provisional Applications 60/678,615, filed May 6, 2005 and 60/678,597,filed on May 6, 2005, the entire content of each application isincorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a clinical diagnostic analyzer for analyzingfluid samples such as patient blood samples. More particularly, theinvention relates to a closed tube sample collecting device including apiercing probe and sample probe assembly mounted on a clinicaldiagnostic analyzer for accessing a fluid in vial, venting mechanismsassociated with the closed tube sample collecting device, and methodsfor sampling and clearing a closed tube sample collecting device betweenpatient samples to prevent cross contamination of the blood samples.

BACKGROUND OF THE INVENTION

Blood and other bodily fluids handled in large quantities by medicallaboratories for processing and testing present cost containment andbiohazard issues for the laboratory. In order to minimize costs oftesting fluids, the equipment and procedures utilized to process suchsamples are becoming increasingly automated so as to permit theprocedures to be performed as quickly as possible with minimum labor.Automating sample processing has the additional benefit of minimizingthe handling of blood and other bodily fluids that are now classified ashazardous substances.

In order to analyze samples of patient fluids, including human blood, asample must first be taken from the patient. Usually the sample ishoused within a container to be aspirated from during analyzeroperation. These sample containers are then loaded into an automaticsample analyzer. If the sample container is capped, the cap must firstbe removed before a sample can be aspirated for analysis. This can bedone manually by the operator, or, if the sample container has afrangible seal, the analyzer may contain a piercing apparatus to breakthe seal on the container to allow aspiration of a fluid sample.

Currently available commercial sample analyzers capable of piercingsealed containers have several disadvantages that reduce theeffectiveness and efficiency of the sampling and analysis operations.For example, some analyzers use the sample aspirator in a dual mode tobreak the frangible seal, as well as to aspirate sample. The use of thesample aspirator in the dual mode may cause blockage of the sampleaspirator if fragments of the seal enter the tip of the aspirator or theventing apertures disposed on the sample aspirator. Additionally, evenif a separate piercing apparatus is used to break the frangible seal,when the sample aspirator alone subsequently enters the perforated seal,debris from the seal can block the sample aspirator tip and/or anyventing ports disposed thereon, thus reducing the accuracy of the samplevolume aspirated, and potentially damaging the sample aspirator. Cloggedventing ports and aspirator tips increase the risk ofcross-contamination of patient samples and also require that more timebe dedicated to cleaning of the apparatus, thus increasing throughputtimes and decreasing the effectiveness of the analyzer.

Furthermore, some analyzers use a piercing device that is separated fromthe sampling device. In some devices, the piercing device is located inclose proximity to the sampling device; however, in some devices thepiercing device and sampling device may be located in different areas ofthe analyzer. Consequently, additional time is required to firstposition the sample tube for piercing and to then either reposition thesample in relation to the sample aspirator, or to move the sampleaspirator to the location of the sample vial. These movements increasethe throughput time of the sample analyzer, thus decreasing itsefficiency.

In addition, currently available sample analyzers may only be able toaspirate sample from one type of vial or sample container at a time.Consequently, if an operator had multiple samples in different sizedvials, only similar containers could be processed in the same batch. Anew cycle or additional analyzer calibration would be required for eachstyle of vial present. The inability of a sample analyzer to processdifferent sized vials in the same batch negatively affects thethroughput time of the analyzer, decreasing its efficiency.

There is, therefore, a demonstrated need in the art for a more efficientautomated sample analyzer with improved throughput rates and improvedprobe designs. The improved sample analyzer reduces or eliminates theproblems associated with current devices used to pierce sample vialcaps, reduces clogging of both the piercing and sampling mechanismsthereby reducing cross-contamination, improving the accuracy ofaspirating sample volumes, and improves access to samples in a varietyof differently sized sample tubes.

SUMMARY OF THE INVENTION

The present invention provides a clinical diagnostic analyzer comprisingan assembly for obtaining a sample of fluid from a fluid sample tube orvial. The invention also provides a method for sampling fluid from afluid sample tube or vial.

In one aspect, the invention provides a clinical diagnostic analyzercomprising a sample collecting device for sampling fluid in a container.In one embodiment, the device includes a first tube comprising a lumenand a piercing end, a second tube comprising a lumen and a free end, anda valve operatively joined to the piercing tube, the valve comprising anopen position and a closed position, and a positive pressure gas sourcefor generating positive gas pressure operatively joined to the valve.The positive gas pressure generated by the positive pressure gas sourcepurges the piercing tube lumen when the valve is in the open position.The second tube is at least partially housed within the lumen of thefirst tube and the free end of the second tube transitions from anenclosed position within the lumen of the first tube to a deployedposition beyond the piercing end of the first tube. At least one of thefirst or the second tube axially moves relative to the other. The secondtube samples fluid in the container when the free end of the second tubeis deployed relative to the piercing end of the first tube.

In one embodiment, the first tube and the second tube movesimultaneously with one another, while in another embodiment, the secondtube is stationary and the first tube moves relative to the second tube.In yet another embodiment, the first tube is stationary while the secondtube moves relative to the first tube.

In another embodiment, the second tube is coupled to an assembly forpassing a gas, e.g., air through the lumen of the second tube, while inyet another embodiment, the first tube is coupled to an assembly forpassing a cleaning solution through the lumen of the first tube.

In another embodiment, the apparatus includes a mechanism for triggeringthe apparatus to pierce the cap of and sample from a sample tube. Themechanism includes a sensor system and an activating member thattriggers the apparatus when the member contacts the sample tube. Themember may be a foot assembly.

In a further embodiment, the piercing end of the first tube is cut on anangle to reveal an elliptical cross section. The end is beveled.

In another embodiment, the apparatus is coupled to a first carriageassembly to permit movement of the apparatus in a first axis of theanalyzer, while in a further embodiment, the first carriage assembly iscoupled to a second carriage assembly to permit movement of theapparatus in a second axis of the analyzer. The analyzer may alsocomprise at least one motor and a computer. In another embodiment, theapparatus further comprises an information processing unit for receivingand sending information to a computer.

In another embodiment of the invention, the first tube may be coupled toa spring-loaded assembly.

According to another embodiment of the invention, the valve of thedevice is a two-way valve. The device may include one, two, or moretwo-way valves arranged in series or in parallel. According to anotherembodiment, the first valve is operatively joined to the positivepressure gas source and the second valve is operatively joined to roomair at atmospheric pressure. According to an alternative embodiment, thevalve is a three-way valve and the three way valve is operatively joinedto the piercing tube, to the positive pressure gas source, and to roomair at atmospheric pressure.

According to another embodiment of the invention, the sample collectingdevice further includes an accumulator. The accumulator is operativelyjoined to the valve and to the positive pressure gas source. Theaccumulator is pressurized from about 25 PSIA to 30 PSIA; preferably 27PSIA. According to another embodiment, the device further includes a gaspressure sensor. The gas pressure sensor is operatively joined to thepositive pressure gas source.

In another embodiment, the present invention provides a clinicaldiagnostic analyzer including an apparatus for sampling fluid in acontainer. The apparatus includes a first non-perforated tubereciprocally movable in a vertical axis comprising a lumen, a piercingend and another end in communication with a conduit, and a secondnon-perforated tube comprising a lumen and a free end. The second tubeis inseparable during sampling from, and is at least partially housedwithin the lumen of the first tube. The free end of the second tubetransitions from an enclosed position within the lumen of the first tubeto a deployed position beyond the piercing end of the first tube. In oneembodiment, the first tube moves axially relative to the second tube. Inanother embodiment the second tube moves axially relative to the firsttube or alternatively, both tubes move axially relative to each other.The second tube samples fluid in the container when the free end of thesecond tube is deployed relative to the piercing end of the first tube.

In one embodiment according to the invention, the piercing end of thefirst tube may be for example, beveled, cut at an angle to reveal anelliptical cross section, chamfered, or the inner edges of the free endmay be rounded.

In one embodiment, the clinical diagnostic analyzer according to theinvention includes a spring operatively joined to the first tube toeffect movement of the first tube. The first tube may further featureone or more detents for positioning the first tube in its vertical axis.In a particular embodiment, the analyzer includes a sensor system thatengages a member contacting the sample tube to determine when a sampletube is in position for piercing and sampling. The member may be, forexample, a foot assembly comprising a through hole.

In one embodiment, the apparatus of the clinical diagnostic analyzer iscoupled to a first carriage assembly to permit movement of the apparatusin a first axis of the analyzer. In another embodiment, the firstcarriage assembly is coupled to a second carriage assembly to permitmovement of said apparatus in a second axis of said analyzer.

In one embodiment the clinical diagnostic analyzer according to theinvention includes a washing station. The washing station may include awashing container, a radial rinser, a filter, and/or a gas jet, or anycombination of the above. In one embodiment the filter is disposed inthe lumen of the washing container. The radial rinser features aplurality of radially arranged rinser ports. The apparatus according tothe invention may further include an air purge system comprising a tubewith an orifice positioned adjacent the tip of the first tube, the airpurge system operatively joined to a gas source

In another embodiment, the clinical diagnostic analyzer includes apressurized gas source in communication with the lumen of the first tubefor purging residual fluid in the lumen. In yet another embodiment, theclinical diagnostic analyzer features a second tube coupled to anassembly for passing fluid through the lumen of the second tube.

In one embodiment of the invention, the first tube is operatively joinedto a sensor to detect contact of the first tube with a fluid or a solid.Alternatively, the second tube is operatively joined to a sensor todetect contact of the second tube with a fluid or a solid. In yetanother embodiment the first tube and the second tube are joined by acircuit to prevent signal of false detection of the other tube.

Other aspects of the present invention will be apparent to these skilledin the art upon reading the following description and claims. While thedescription and drawings are of a particular embodiment, otherembodiments fall within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like reference characters generally refer to the sameparts throughout the different views. Also, the drawings are notnecessarily to scale, emphasis instead generally being placed uponillustrating the principles of the invention.

FIG. 1 is a schematic view of a clinical diagnostic analyzer including asample collecting device according to an illustrative embodiment of theinvention.

FIG. 2A is a front perspective view of an exemplary closed-tube samplingassembly of the invention housed within a clinical diagnostic sampleanalyzer.

FIG. 2B is a side, partial cutaway view of the washing station shown inFIG. 2A according to the invention.

FIG. 3 depicts an exemplary piercing probe of the invention.

FIG. 4A shows a cutaway view of a portion of an exemplary piercing probeincluding a blunt tip and chamfered edge.

FIG. 4B shows a side view of the portion of the exemplary piercing probeof FIG. 4A.

FIG. 4C shows a side view of a portion of an exemplary piercing probewith a double-pointed tip 32.

FIG. 5 depicts an exemplary sample probe of the invention.

FIG. 6 depicts a partial cut-away side view of the distal portion of anexemplary sample probe according to the invention, housed within thelumen of the distal portion of an exemplary piercing probe of anexemplary sampling assembly of the invention.

FIG. 7 shows a perspective view of the distal portion of an exemplarysample probe housed within the lumen of the distal end and extendedbeyond the opening of an exemplary piercing probe according to theinvention.

FIG. 8 shows a perspective view of the distal portion of an exemplarysample probe housed and completely enclosed within the lumen of thedistal end of an exemplary piercing probe according to the inventionwherein the distal portion of the sample probe is enclosed.

FIG. 9A is a perspective view of a sampling assembly including anexemplary closed-tube piercing probe and sample probe of the inventionin an unreleased position.

FIG. 9B is a perspective view of the proximal portion of samplingassembly including the exemplary closed-tube piercing probe and sampleprobe assembly of FIG. 9A.

FIG. 10 is a schematic view of a portion of the sample collecting devicein FIG. 1 including a first valve and a second valve according to anillustrative embodiment of the invention.

FIG. 11 is a schematic view of a portion of the sample collecting devicein FIG. 1 including a valve according to another illustrative embodimentof the invention.

FIG. 12 is a perspective view of an exemplary closed-tube piercing probeand sample probe assembly sampling assembly of the invention wherein thetip of the piercing probe and the tip of the sample probe are exposed.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is related to a telescoping piercing probe andsample probe assembly and a venting mechanism mounted on a clinicaldiagnostic analyzer for automated piercing and sampling of fluid in avial. The assembly includes a sample probe housed within a piercingprobe. All of the following embodiments of the invention includefeatures that improve the efficiency and effectiveness of an automateddiagnostic sample analyzer including the piercing probe and sample probeassembly, and the venting mechanism of the invention.

Referring to FIG. 1, a sample collecting device 18, for example, aclosed tube sample collecting device, is a component of an automatedclinical diagnostic analyzer 10 that analyzes patient blood samples. Theclinical diagnostic analyzer 10 may further include an analysis station4, a wash station 9, a processor 8, a drive motor 90 and a sample tuberack 96. The sample tube rack 96 includes a plurality of sample tubewells 98. A patient blood sample, contained within a sample tube 7,rests within a sample tube well 98. It is contemplated that the samplecollecting device 18 may collect samples from a variety of sized andshaped sample tubes 7, including both closed sample tubes 7, cups (notshown), vials (not shown), and open sample tubes. The closed sampletubes 7 include a sample tube cap or seal 37 to seal the sample from theatmosphere and particulate debris.

Referring still to FIG. 1, in one embodiment according to the inventionthe sample collecting device 18 includes a sampling assembly 3comprising a piercing tube 36 comprising an axially-disposed lumen 35,and a sample aspirating probe 30 including an axially disposed lumen 33.In a further embodiment, the sample collecting device 18 may alsoinclude one or more valves 40, an accumulator 62, and a positivepressure gas source 70.

With reference to FIG. 2A, in one embodiment, the sampling assembly 3 ismounted to a carriage assembly which travels via a bearing rail 5 of anarm 1. The arm 1 is also attached to a second carriage assembly whichtravels on a second bearing rail (not shown).

With continued reference to FIG. 2A, in one embodiment according to theinvention, a cuvette dispenser (not shown) is positioned at the rear ofthe analyzer 10 to dispense cuvettes (not shown) that receive the sampleobtained by the sampling assembly 3. The cuvettes are transported by atube transport mechanism (not shown) to the analysis station 4 such as,for example, a luminometer.

Referring to FIG. 2B, a further embodiment of the analyzer 10 accordingto the invention includes a washing station 9. The washing station 9cleans the piercing probe 36 and sample probe 30 of the samplingassembly 3 after the sample removed from the sample tube 7 is dispensedinto a cuvette (not shown). In one embodiment of the invention, thewashing station 9 includes a container 200 of washing fluid and a spraydevice, e.g., a shower 180 that sprays a washing fluid directed to thecontaminated piercing probe 36 and/or sample probe 30. In anotherembodiment, the washing station 9 further includes a filter 184 forremoving debris. The filter 184 may be substantially cylindrical,disc-shaped or conical. In a particular embodiment the filter iscylindrical and disposed in the lumen of the washing container. In yetanother embodiment, the washing station 9 includes a jet 160 connectedto a gas source (not shown) for directing a blast of drying gas to thedistal end of the piercing probe to dry the probe.

Referring again to FIG. 2A, a computer (not shown) controls the overallactivity of the analyzer 10 by receiving input from the various sensorsand information processing units of the analyzer 10 and directing themovement of the various parts of the analyzer 10, such as the movementof the positioning arm 1 along the rail 5, according to one embodimentof the invention. The movement of the positioning arm 1 is driven by amotor 90. There may also be additional motors to drive movement of otherparts of the analyzer 10. The clinical diagnostic sample analyzer 10shown here is only one example of an analyzer utilizing the samplingassembly 3 of the invention. The sampling assembly 3 may be usedaccording to the invention with any appropriately configured clinicaldiagnostic sample analyzer.

FIG. 3 depicts an exemplary piercing probe 36 of the invention. Thepiercing probe 36 is a tubular structure including a distal end, aproximal end, and an axially disposed lumen 35 that opens on the distaland proximal end of the tubular structure. The walls of the tubularstructure are non-perforated; i.e., without holes, ports or vents. Inone embodiment, the piercing probe 36 is reciprocally movable in avertical axis.

According to another embodiment, a tip 32 for piercing a sample tube 7is disposed at the distal end of the piercing probe 36, while thepiercing probe 36 proximal to the tip 32 has at least a first detent 42and a second detent 44 proximal to the first detent 42. Additionaldetents may also be included in the probe 36 according to alternativeembodiments of the invention. According to a particular embodiment, thepiercing probe 36 includes only one detent (not shown). The first andsecond detents assist in positioning the piercing probe 36 relative tothe sampling probe 30 and will be discussed further below. The proximalend of the piercing probe 36 also may be in communication with aconduit.

While in one embodiment of the invention, the tip 32 of the piercingprobe 36 shown in FIG. 3 is beveled and reveals an ellipticalcross-section, the tip 32 may be cut at any angle. As shown in FIGS.4A-C, the tip may also be one of a variety of different shapes, e.g.,diamond, circular, oval, rectangular, toothed and scalloped, forexample. FIG. 4A shows a cutaway view of the distal portion of anexemplary piercing probe 36 including a blunt tip 32 that includes achamfered edge according to one embodiment of the invention. FIG. 4Bshows a side view of the portion of the exemplary piercing probeillustrated in FIG. 4A. In another embodiment, FIG. 4C shows a side viewof the distal portion of a piercing probe 36 is a double-pointed tip 32.In yet another embodiment, the tip 32 of the piercing probe 36 hasmultiple points. In another embodiment, the internal edges of the tip 32of the piercing tube 36 are rounded (not shown). In one furtherembodiment, the tip 32 of the piercing probe 36 reduces coring of thesample tube cap 37, thus the end surface of the tube may have one ormore cuts or be sharpened to reduce coring. Any configuration of tip 32capable of perforating a seal 37 of a sample tube 7 may be used.

FIG. 5 depicts an exemplary sample probe 30 of the invention. The sampleprobe 30 is a tubular structure including an axially disposed lumen, aproximal end 28, and a distal free end 34. The sample probe 30 isaxially disposed in and inseparable from the lumen 35 of the piercingprobe 36 during the sampling step. The lumen 34 of the sample probe 30opens at the distal and proximal end of the tubular structure. The wallsof the tubular structure of the sample probe 30 are non-perforated,i.e., without holes, ports or vents. The free end 34 includes an openingfor fluid communication between the probe lumen 33 and the exterior ofthe probe 30. The free end 34 of the probe is inserted into a sample toaspirate a sample from a sample vial 7. In one embodiment, the proximalend 28 of the sample probe 30 is coupled to a seal assembly 26 whichwill be discussed in detail below. The proximal end 28 of the sampleprobe 30 is connectable to a supply tube or other supply member that mayserve as a conduit for the introduction of fluids or gases for cleaningor rinsing the lumen 33 of the sample probe 30 or for transport of fluidby the sample probe 30, for example, to or from a sample tube 7.

FIG. 6 illustrates a partial cut away side view of the distal portion ofan exemplary sample probe 30, housed within the lumen 35 of the distalportion of an exemplary piercing probe 36 of a sampling assembly 3according to one embodiment of the invention. As shown in FIG. 6,according to one embodiment of the invention, when the sample probe 30is positioned in the sample vial 7, the piercing probe 36 encloses thesample probe 30 to prevent the sample probe 30 from contacting the seal37 of the sample vial 7. The barrier formed by the piercing probe 36prevents pieces of the frangible seal 37 from partially or completelyclogging or blocking the opening of the sample probe lumen 33 at the tip34 of the sample probe 30. Furthermore, because the sample probe 30never touches the seal 37 of the sample vial 7, the surface area of thesample probe 30 that would otherwise require cleaning is minimizedthereby decreasing wash time and quantity of wash fluids required,thereby improving the overall efficiency of the analyzer 10.

In addition, in one embodiment according to the invention, the lumen 35of the piercing probe 36 acts as a vent for the sample tube 7. Ventingof the sample tube 7 is advantageous because venting equalizes thepressure inside the sample tube 7 with the pressure outside the sampletube 7 to ensure the accuracy of aspiration volumes. By eliminatingventing ports on the piercing probe 36 that would otherwise be requiredto permit venting, the likelihood that fragments of the seal 37 willclog the piercing probe 36 is minimized. Reduced sample probe 30clogging allows for greater sampling accuracy and reduce the possibilityof damage to the sample probe 30, in particular, the sample probe tip34. In addition, reduced clogging decreases the amount of time requiredto clean the sample probe 30 and the piercing probe 36, therebyimproving the overall efficiency of the sample analyzer 10.

FIG. 7 shows a perspective view of the distal portion of an exemplarysample probe 30 housed within the lumen 35 of the distal portion of anexemplary piercing probe 36 according to the invention. The tip 34 ofthe sample probe 30, illustrated in FIG. 7, is exposed in the opening ofthe lumen 35 at the distal tip 32 of the piercing probe 36.

FIG. 8 shows another perspective view of the exemplary sample probe 30housed within the lumen 35 of an exemplary piercing probe 36 of theinvention. As shown in FIG. 8, the tip 34 of the sample probe 30 (shownin outline) is withdrawn proximally into the lumen 35 of the piercingprobe 36 where it is enclosed by the distal portion of the piercingprobe 36 and is not exposed in the opening of the lumen 35 of the distaltip 32 of the piercing probe 36. The sample probe 30 and the piercingprobe 36 are axially slideably moveable relative to one another. Forexample, by withdrawing the piercing probe 36 proximally, andmaintaining the sample probe 30 stationary, the distal tip 34 of thesample probe 30 is positioned, i.e., exposed in the opening of the lumen35 of the distal tip 32 of the piercing probe 36. Alternatively, thesample probe 30 is advanced distally while the piercing probe 36 remainsstationary. In yet another embodiment of the invention, both the sampleprobe 30 and the piercing probe 36 are slideably moveable. Because ofthe relative movement of the sample probe 30 and the piercing probe 36,when the piercing probe 36 punctures the seal 37 on the sample tube 7,the distal tip 34 of the sample probe 30 is positioned i.e., enclosedwithin the lumen 35 of the piercing probe 36 and not extended beyond thetip 32 of the piercing probe 36, as shown in FIG. 8. When ready toaspirate the sample from the sample tube 7, the distal tip 34 of thesample probe 30 is positioned below, i.e., extended beyond the piercingprobe tip 32, as shown in FIG. 6, positioned within or within theopening of the lumen 35 of the tip 32 of the piercing probe 36. Whilethe tip 32 of the piercing probe 36 may encounter sample during theprocess of piercing the seal 37, portions of the piercing probe 36proximal to the tip 32 are not immersed in sample. By minimizing thesurface area of the piercing probe 36 that is exposed to sample, thesurface area of the piercing probe 36 that requires cleaning is reduced.

FIG. 9A is a perspective view of an exemplary closed-tube piercing probeand sample probe assembly of the invention in an unreleased position.FIG. 9B is a perspective view of the proximal portion of the exemplaryclosed-tube piercing probe and sample probe assembly of FIG. 9A. In theunreleased position shown in FIG. 9A, both the tip 32 of the piercingprobe 36, and the tip 34 of the sample probe 30 are enclosed. The tip 32of the piercing probe 36 is covered by the foot 22 and tip 34 of thesample probe 30 is housed within the piercing probe 36.

With continued reference to FIG. 9A, the foot 22 has a lumen (bestillustrated in FIG. 2B) through which the piercing probe 36 housing thesample probe 30 pass. According to one embodiment of the invention, thefoot 22 is coupled to a brake rod 21. The brake rod 21 and the foot 22move independently of the other elements of the sampling assembly 3 andhold the sample tube 7 in place while the sampling cycle occurs. In afurther embodiment, the brake rod 21 may be attached to the positioningarm 1.

With continued reference to FIG. 9A and FIG. 9B, according to oneembodiment of the invention, the sampling assembly 3 includes a sealassembly 26 that engages the proximal end 41 (See FIG. 3) of thepiercing probe 36, scaling the proximal end 41 from the externalenvironment. In one embodiment, the seal assembly 26 provides an orifice49 for the introduction of fluids or gases for cleaning the lumen 35 ofthe piercing probe 36. In one embodiment, the proximal end 28 of thesample probe 30 serves as an entrance point 28 for the introduction offluids or gases that may be used, for example, to clean the lumen of thesample probe 30.

Referring back to FIG. 1 according to one embodiment, the proximal end41 of the piercing probe 36 of the sampling assembly 3 sealingly joinsto a length of tubing 80. The tubing 80 may be formed of a polymer, suchas Tygon™. The tubing 80 connects the proximal end 41 of the piercingprobe 36 at the orifice 49 of the seal assembly 26 so as to be in fluidcommunication with the positive pressure gas source 70. The tubing 80may be in the form of a single length of tubing, or in multiple lengthsof tubing sealingly joined by additional orifices, gaskets, valves, orother sealable junctions.

With continued reference to FIG. 1, in certain embodiments, the samplecollecting device 18 includes an accumulator 62 to contain pressurizedair or other gaseous fluid. The accumulator 62 is sealingly joined,through a length of tubing 80, to the sampling assembly 3 on one end andto the positive pressure gas source 70 on the other end. The accumulator62 is a container capable of containing a volume of pressurized gas andmaintaining the pressurized gas at a desired magnitude of positivepressure. According to one embodiment of the invention, the accumulator62 is capable of containing a volume of gas in the range of about 200 ccto 500 cc, most preferably 300 cc.

With continued reference to FIG. 1, according to one embodiment of theinvention, the positive pressure gas source 70 is, for example, apositive pressure gas pump, capable of generating pressurized gas.According to an alternative embodiment, pressurized gas is provided tothe sample collecting device 18 through a remote positive pressure gassource, such as a centralized “in house” pressurized gas line, in fluidcommunication with the lumen 35 of the piercing probe. In oneembodiment, the positive pressure gas source 70 is provided with orwithout an accumulator 62.

In another embodiment of the invention, referring still to FIG. 1, theaccumulator 62 includes a gas pressure meter 66 and/or a gas pressuresensor 72. The exemplary gas pressure meter 66 provides a visual displayof the current gas pressure within the accumulator 62. The gas pressuresensor 72 measures the gas pressure within the accumulator 62 andprovides a signal to the positive pressure gas source 70, for example, apositive pressure air pump. When the gas pressure in the accumulator 62falls below the desired gas pressure magnitude, the sensor 72 signalsthe gas source 70 to switch on and to increase the gas pressure withinthe accumulator 62. Once the gas pressure sensor 72 measures a gaspressure at the desired magnitude, the sensor 72 signals the gas source70 to switch off. The combination of the sensor

72 and the gas source 70 maintains a near constant desired gas pressurewithin the accumulator 62. According to one embodiment of the invention,the gas pressure within the accumulator 62 is preferably in a range fromabout 25 PSIA to 30 PSIA, more preferably from about 27 PSIA to 28 PSIA,and preferably 27 PSIA.

Referring still to FIG. 1, according to one embodiment of the invention,the sample collecting device 18 includes a valve 40. The valve 40reversibly alternates between an open position and a closed positionthrough the movement of a switch 42. When the valve 40 is in the openposition, the lumen 35 of the piercing tube 36 is in communication withthe valve 40, and the tubing 80 between the free end 32 of the piercingtube 36 and the accumulator 62. When the valve 40 is in the closedposition, the gas pressure in the lumen 35 between the valve 40 and thetip 32 of the piercing tube 36 maintains a first gas pressure, equal toatmospheric pressure at the free end 32 of the piercing tube 36. Whenthe valve 40 is in the closed position, the gas pressure present betweenthe valve 40 in the lumen 31 of the tubing 80 to the accumulator 62maintains a second gas pressure, equal to the gas pressure generated bythe positive pressure gas source 70.

Referring now to FIG. 10, the sample collecting device 18, according toan alternative embodiment, includes a first valve 40 and a second valve50. According to this embodiment, the first valve 40, a two-way valve,opens and closes a fluid communication between the lumen 31 of the gastubing 80 and the pressurized gas within the accumulator 62. The secondvalve 50, a three-way valve, opens and closes a fluid communicationbetween the lumen 31 of the gas tubing 80 and an orifice 56 open to roomair at atmospheric pressure. Accordingly, in the closed position, theorifice 56 of the second valve 50 is no longer patent (open), i.e., itis closed. When the first valve 40 is in the closed position and thesecond valve 50 is in the closed position, the pressure in the lumen 31is equal to atmospheric pressure, i.e., the gas pressure at the onlyorifice that is open, the open end 32 of the piercing tube 36 (shown inFIG. 1).

With continued reference to FIG. 10, when the first valve 40 is in theopen position and the second valve 50 is in the closed position, thepressure within the lumen 31 between the second valve 50 and theaccumulator 62 equals the pressure of the gas pressure contained withinthe accumulator 62. When the first valve 40 is initially opened, thelumen 31 experiences a sudden burst of positively pressurized gas. Asthe first valve 40 remains open, the pressure of the gas decreases untilthe entire system, including the lumen 31 and the open gas accumulator62, equalize towards the gas pressure at the open end 32 of the piercingtube 36 (shown in FIG. 1). According to one embodiment of the invention,the first valve 40 is only opened for a few milliseconds, permitting ashort blast of positively pressured gas to escape and to purge the lumen35 of the piercing tube 36 and to dry the outside tip of the piercingtube 36, but maintaining sufficient gas pressure within the accumulator62 for subsequent blast cycles without requiring substantial rechargingof positive pressure by the gas source 70. According to one embodimentof the invention, the first valve 40 is opened from 10 milliseconds to 4seconds; more preferably 30 milliseconds to 2 seconds; and mostpreferably 50 milliseconds to 1 second.

Referring still to FIG. 10, when the first valve 40 is in the closedposition and the second valve 50 is in the open position, the gas withinthe lumen 31 of the tubing 80 and the piercing tube 36 (not shown) is ata gas pressure equal to atmospheric pressure. Referring again to FIG. 1,when the free end 32 of the piercing tube 36 is outside the sample tube7, the pressure within the lumen 35 of the piercing tube 36 is equal toatmospheric pressure. Alternatively, when the free end 32 of thepiercing tube 36 is extended into the sample tube 7, the pressure withinthe lumen 35 of the piercing tube 36 will equilibrate with the pressure,either positive or negative, of the sample tube 7. For example, if thesample tube 7 is sealed with a sample tube cap 37, the sample tube 7 mayhave an internal gas pressure either higher or lower than atmosphericpressure. Additionally, aspiration of a sample from the sample tube 7 bythe sample probe 30 may lower the gas pressure within the sample tube 7,and subsequently within the lumen 35 of the piercing tube 36, to a gaspressure below atmospheric pressure. In this situation, the pressurewithin the free end 32 of the piercing tube 36 will equilibrate withatmospheric pressure, by venting through the open orifice 56 of thesecond valve 50.

Gas pressures remaining in the sampling assembly either above or belowatmospheric pressure may introduce errors in the amount of sampleaspirated. For example, an automated aspirating probe may be programmedto aspirate sample for a predetermined period of time or for apredetermined volume, such that a standardized sample volume isaspirated during each procedure. If the sample is aspirated at a gaspressure either above or below atmospheric pressure, a timed sampleaspiration may result in either too much or too little sample beingaspirated, introducing errors into subsequent analyses. A vent toatmospheric pressure reduces the likelihood that such a sampling errorwill occur.

Now referring to FIG. 11, in an alternative embodiment, the samplecollecting device 18 includes a single three-way valve 100 connectingthe lumen 35 of the piercing tube 36 (not shown) to the accumulator 62and also to an orifice 56 open to room air at atmospheric pressure.According to one embodiment of this invention, the three-way valve 100includes a single toggle switch 92 alternating fluid communicationbetween the lumen 35 of the piercing tube 36 and either the accumulator62 or the atmosphere. According to an alternative embodiment, the valve100 includes two toggle switches 94, 96 allowing three states of fluidcommunication. When both switches 94, 96 are in their closed positions,the lumen 35 of the piercing tube 36 (not shown) is only open at itsfree end 32 and the gas pressure within the lumen 35 tends toward(atmospheric pressure,) the gas pressure at the free end 32. When thefirst switch 94 is in its closed position and the second switch 96 is inits open position, the gas pressure in the lumen 31 tends towardatmospheric pressure. When the first switch 94 is in its open positionand the second switch 96 is in its closed position, the lumen 35 isexposed to the pressurized gas stored in and released from theaccumulator 62. It is contemplated that alternative valve schematics,including at least one three-way valve or at least two two-way valvescombinations of two-way and three-way valves, may be utilized that allowalternation between the at least two desired states.

Referring now to FIG. 12, in one embodiment according to the invention,the sampling assembly 3 includes a solenoid 25 which controls a lock 24for engaging the upper detent 44 or the lower detent 42 of the piercingprobe 36.

In one embodiment according to the invention, the sample probe 30 iscoupled to the sampling assembly 3 via the seal assembly 26. Verticalmovement of the piercing probe 36 is necessary to expose or enclose,i.e., cover the distal end 34 of the sample probe 30. When the lock 24engages the upper detent 44, the piercing probe 36 is locked in loweredposition such that the tip 34 of the sample probe 30 is enclosed withinthe lumen 35 of the piercing probe 36 and is not exposed. If the lock 24engages the lower detent 42, the piercing probe 36 is locked in a raisedposition, exposing the distal end 34 of the sample probe 30. Thus, inone embodiment, the sample probe 30 remains in a constantly fixedposition relative to the sampling assembly 3, while the piercing probe36 moves relative to the sample probe 30 and the sampling assembly 3.However, in another embodiment, the sample probe 30 may alternatively bedesigned to move relative to a piercing probe 36 fixed in a constantposition relative to the sampling assembly 3. In a further embodiment,neither the sample probe 30 nor the piercing probe 36 are fixed, butboth are capable of movement relative to the other and relative to thesampling assembly 3.

With continued reference to FIG. 12, in one embodiment of the invention,the sampling assembly 3 includes an information processing unit 8, suchas, for example, a PC board, controller or digital signal processor,which sends to and receives information from various sensors 45associated with the sampling assembly 3. The information processing unit8 also controls a solenoid 25 which operates to release or engage thelock 24. In addition, in one embodiment according to the invention, theinformation processing unit 8 communicates with a main computer (notshown) operating the analyzer.

With continued reference to FIG. 12, the sampling assembly 3 is attachedto the positioning arm 1 by a z-rack 23, according to one embodiment ofthe invention. A motor (not shown) on the positioning arm 1 drives thez-rack 23 up and down in the z-axis (vertical), thus moving the samplingassembly 3 up and down in the z-axis, thereby moving the sample probe 30and the piercing probe 36 upwards or downwards, piercing the cap 37 ofthe sample tube by the piercing probe 36 and sampling the patient fluidin the vial 7 by the sample probe 30. In one embodiment according to theinvention, the sample probe 30 and/or the piercing probe 36 is incommunication with a sensor (not shown) that detects contact of thesensor probe 30 with a fluid or a solid. As used throughout thespecification, the term sensor includes optical, mechanical, orelectromechanical sensors, for example. A sensor may also be a circuitthat detects a shift in capacitance. For example, a sensor may detectmotion parallel to the length of the sample probe 30 or piercing probe36 to move the apparatus to detect the head of shoulder screws todetermine the coordinates of target locations. The same motion may beused to detect fluid in tubes, cups or the cuvette. Alternatively,motion normal to the length of the probes may be used. In yet anotherembodiment, the sampling probe 30 and the piercing probe 36 are joinedby, for example, a circuit, connector or cable to detect motion betweenthe sample probe 30 and piercing probe 36 to ensure motion between theprobes does not cause false detection of fluid thereby to eliminatefalse liquid level detection.

In one aspect, the invention is a method for automated sampling ofpatient fluid by the clinical diagnostic analyzer including a samplecollecting device. In order to obtain the sample from a sample tube 7containing the patient sample, the seal 37 of the sample tube 7 mustfirst be pierced by the tip 32 of the piercing probe 36. Before piercingthe seal 37, the sample probe 30 is locked in a retracted position toprevent damage to the sample probe while the seal 37 is pierced.

Referring to FIGS. 9A and 9B, in a first position, the upper detent 44of the piercing probe 36 is engaged by the lock 24. This positions thesample probe 30 in a retracted position relative to the piercing probe36, for example as shown in FIG. 9A, such that the tip 34 of the sampleprobe 30 is enclosed by the piercing probe 36 and will not be exposed ordamaged during the seal 37 piercing step.

With continued reference to FIG. 9A, in order for the piercing probe 36to pierce the seal 37 of a sample tube 7, the foot 22 first contacts theseal 37. When the foot 22 contacts the top of a sample tube 7, the brakerod 21 moves upward in the z-axis, releasing a flag from the sensor 47.This causes the z-rack 23 to drive downward and moves the piercing probe36 through the lumen of the foot 22 to perforate the seal 37 of the tube7. In one embodiment of the invention, the piercing probe 36 may bespring-loaded to permit movement of the piercing probe 36 upward whensampling from uncapped sample tubes 7. When accessing samples in cappedtubes 7, once the piercing probe 36 enters the cap 37, friction preventsthe spring from releasing and moving the piercing probe 36 upwards.Therefore, once the seal is broken, the z-rack 23 drives upward,allowing the lock 24 to release and the spring (not shown) to expand,moving the piercing probe 36 upward to expose the sample probe 30 housedwithin. During this step, the tip 32 of the piercing probe 36 remains inthe sample tube 7. The lock 24 then reengages the piercing probe 36 inthe lower detent 42. The z-rack 23 subsequently drives the samplingassembly 3 downward so that the tip 34 of the sample probe 30 canaspirate the sample in the tube 7. The z-rack 23 then drives upwardallowing the sample probe 30 and piercing probe 36 to exit the sampletube 7 simultaneously. The foot 22 strips the sample tube 7 from thepiercing probe 36 as the piercing probe 36 is driven upward by thez-rack 23.

Referring back to FIG. 2A, the sampling assembly 3 then moves to anotherlocation of the analyzer 10 to release the sample into a cuvette 108. Tomove in the x-axis and y-axis, the sampling assembly travels along thez-axis of the positioning arm 1, while the positioning arm 1 movessimultaneously along the x-axis of the rail 5.

With reference to FIG. 2B, in one embodiment according to the invention,the wash station 9 includes a deep washer for deep washing the distalportion 34 of the sample probe 30 and the distal portion 32 of thepiercing probe 36. The deep washer includes a radial rinser for 180rinsing the exterior of the piercing probe 36, the interior of thepiercing probe 36 tip 32 and the exterior of the sample probe 30 tip 34.The radial rinser is attached to a radial rinse pump (not shown) whichis activated when the piercing probe is brought up in the z-axis. Theradial rinser 180 sprays a radial shower of rinse solution through aplurality of radially arranged rinse ports 182. The deep washer 9 mayfurther feature an internal sample probe rinser.

The lumen 33 of the sample probe 30 is washed by a stream of rinse fluidpassed through the lumen 33 of the sample probe 30 in fluidcommunication with a sample probe rinser pump. The flow rate of rinsefluid through the lumen 33 of the sample probe 30 is in the range ofabout 0.25 to 2.0 ml/second, preferably about 1.0 to 1.5 ml/second, morepreferably 1.05 ml/sec.

In a further embodiment, an air pump or gas source 70 such as, forexample, the gas source 70 described above with respect to the ventingmechanism, is joined in fluid communication with the lumen 35 of thepiercing probe 36. The pressurized gas from the gas source 70 purgesresidual fluid from the annular area between the sample probe 30 and thepiercing probe 36 after a deep wash cycle. The gas source 70 is requiredto maintain a clear vent path needed during aspiration in the closedtube system described herein. Without a clear vent path, the internalpressure of the sample tube will not be at atmospheric pressure. Apartial tube pressure above atmospheric leads to over aspiration; apartial vacuum leads to under aspiration. A clear vent path allows theimmediate pressure equalization inside the sample tube and maintainsgood precision and accuracy for sampling.

In a further embodiment according to the invention, the gas source 70 isan air purge system such as a jet including a tube 160 with an openingpositioned adjacent the piercing probe tip that supplies a short burstof air through an orifice in the foot 22 to the outside of the piercingprobe tip. The short burst of air removes any residual rinse fluid thatmay remain on the piercing probe tip after the deep wash.

In another embodiment, the deep washer 9 includes a replaceable filter184 for removing debris following piercing of the sample tube seal bythe piercing probe 36. The debris is material displaced from the tubecap generated during the piercing process. The filter prevents thedebris from blocking tubing to and from the washer. The filter isreplaceable by laboratory personnel avoiding costly service calls.Typically, the filter is replaced every 5000 cycles. A verificationsystem such as a sensor may be installed to verify the filter is inplace.

At least one advantage of the sample collecting device 3 according tothe invention is that the sample tube 7 is pierced by the piercing probe36 and the sample fluid is aspirated by the sample probe 30 without theneed for the sampling assembly 3 to move in the x-axis or the y-axis.This feature reduces the time required to obtain a sample aliquot fromthe sample tube 7 and improves throughput time, thus increasing theefficiency of the sample analyzer 10. For example, the table below

PT APTT (tests per hour) (tests per hour) A 270 270 B 228 120

compares the actual throughput of a sample collecting device accordingto the invention (A) for prothrombin time (PT) and activated partialthromboplastin time (APTT) to the actual throughput of a pre-existingsample collecting device (B) for the same tests. The sample collectingdevice according to the invention processes 270 PT tests/hour and 270APTT tests per hour while the pre-existing sample collecting deviceprocesses 228 PT and 120 APTT tests per hour. Thus, the throughput ofthe sample collecting device according to the invention is more thandouble the throughput of the pre-existing sample collecting device.

Furthermore, because the tip 32 of the piercing probe 36 is positionedwithin the sample tube 7 from the initial pierce until the sample isaspirated, the likelihood of contamination that would otherwise resultfrom multiple entries into the sample tube 7 is reduced.

Other advantages of the sampling assembly 3 according to the inventiondescribed herein include the ability of the sample analyzer 10 utilizingthe sampling assembly 3 of the invention to process a batch of sampletubes 7 where some tubes 7 are capped or sealed and some tubes 7 lackcaps or seals. This is possible because the piercing probe 36 and thesample probe 30 can perform the same steps on a sample tube, regardlessof whether a cap is present.

Furthermore, the telescoping configuration of the sample probe 30 andthe piercing probe 36 eliminates the need for movement in the x-axis ory-axis during the piercing and sampling stage enabling the samplingassembly 3 to be more easily centered on a sample tube cap 37.Accordingly, the sampling assembly 3 samples from sample tubes 7 ofdiffering diameters and geometries, as well as samples from sample tubecaps or seals 37 of differing diameters and materials. Furthermore, theability of the sampling assembly 3 to move in the z-axis, allows thesampling assembly 3 to sample from tubes 7 of different heights in thesame batch. Thus, any variety of sample vials may be placed in thesample tube receiving area 102 (see, e.g., FIG. 2A).

While the sampling assembly including the venting mechanism describedherein is preferably used in aspirating a patient sample, the samplingassembly is also useful for aspirating volumes of other fluids orliquids, including reagents, for example. These fluids may be aspiratedfrom any number of containers including, but not limited to vials, testtubes, and sample tubes. Other variations, modifications, andimplementations of what is described herein will occur to those ofordinary skill in the art without departing from the spirit and thescope of the invention as claimed. Accordingly the invention is not tobe defined by the preceding illustrative description, but instead by thespirit and scope of the claims that follow.

What is claimed is:
 1. A method for analyzing a sample in a samplecontainer, comprising: (i) providing a sample collecting devicecomprising a sampling assembly comprising, (a) a first tube comprising alumen and an upper detent and a lower detent; (b) a locking mechanism,(c) a second tube comprising a lumen and a free end, wherein said secondtube is enclosed within the lumen of said first tube; and, (d) a systemfor moving said first tube and said second tube relative to each otherin a vertical axis comprising, a z-rack operatively joined to said firstand second tubes, one or more motion sensors for detecting motionparallel to the length of at least one of the first tube or the secondtube and a foot assembly wherein said one or more motion sensors isengaged by said foot assembly to determine when said container is in aposition for piercing, and a motor operatively connected to said z-rackfor driving said z-rack; (ii) reversibly engaging said locking mechanismwith said lower detent of said first tube; (iii) contacting said footassembly with said sample container; (iv) driving said Z-rack verticallyvia said motor and in response to said sensors, moving said first tubein a vertical axis from a first position to a second position into saidsample container and piercing a seal of said sample container; (v)axially moving the free end of said second tube from an enclosedposition within the lumen of the first tube to a deployed position; (vi)collecting the sample from the sample container with the free end of thesecond tube, wherein said second tube is operatively joined to a pump;(vii) providing an analysis station in communication with said secondtube; and, (viii) analyzing said sample.
 2. The method of claim 1further comprising transporting said sample by the second tube via aproximal end connectable to a supply member that serves as a conduit totransport said sample by the second tube.
 3. The method of claim 1further comprising venting the sample container by the lumen of thefirst tube.
 4. The method of claim 3 wherein said venting equalizesinside pressure of the sample container with outside pressure of thesample container.
 5. The method of claim 1, wherein said sample is apatient fluid.
 6. The method of claim 1 wherein during said collectingstep the free end of the second tube transitions from an enclosedposition within the lumen of the first tube to a deployed positionbeyond a pointed tip of the first tube.
 7. The method of claim 1 whereinprior to said collecting step said second tube is locked in a retractedposition by said locking mechanism.
 8. The method of claim 1 whereinsaid upper and said lower detents position the first tube relative tothe second tube.
 9. The method of claim 1 wherein the first tube islocked in lowered position such that a pointed tip of the second tube isenclosed within the lumen of the first tube while the lock engages theupper detent.
 10. The method of claim 1 wherein while the lock engagesthe lower detent, the first tube is locked in a raised position,exposing a distal end of the second tube.
 11. The method of claim 1wherein the second tube remains in a constantly fixed position relativeto the sampling assembly, while the first tube moves relative to thesecond tube and the sampling assembly.
 12. The method of claim 1 whereinthe first tube remains in a constantly fixed position relative to thesampling assembly while the second tube moves relative to the first tubeand the sampling assembly.
 13. The method of claim 1 wherein the firsttube and the second tube move relative to each other and relative to thesampling assembly.